framework/ember/app/styles/flarum/forms.less

.form-group {
  margin-bottom: 12px;
}
.form-control {
  .box-shadow(none);
  &:focus,
  &.focus {
    background-color: #fff;
    color: @fl-body-color;
    .box-shadow(none);
  }
}

// Search inputs
// @todo Extract some of this into header-specific definitions
.search-input {
  overflow: hidden;

  &:before {
    .fa();
    content: @fa-var-search;
    float: left;
    margin-right: -36px;
    width: 36px;
    font-size: 14px;
    text-align: center;
    color: @fl-body-muted-color;
    position: relative;
    padding: @padding-base-vertical - 1 0;
    line-height: @line-height-base;
    pointer-events: none;
  }
  & .form-control {
    float: left;
    width: 225px;
    padding-left: 36px;
    padding-right: 36px;
    .transition(~"all 0.4s");
  }
  & .clear {
    float: left;
    margin-left: -36px;
    vertical-align: top;
    opacity: 0;
    width: 36px !important;
    .rotate(-180deg);
    .transition(~"transform 0.2s, opacity 0.2s");
  }
  &.clearable .clear {
    opacity: 1;
    .rotate(0deg);
  }
}

// Select inputs
.select-input {
  display: inline-block;
  vertical-align: middle;
}
.select-input select {
  display: inline-block;
  width: auto;
  -webkit-appearance: none;
  padding-right: @padding-base-horizontal + 16;
  cursor: pointer;
}
.select-input .fa {
  margin-left: -@padding-base-horizontal - 16;
  pointer-events: none;
  color: @fl-body-muted-color;
}